Canada



(No Model.)

J. S. PARMENTER.

GoMPoUND ENGINE.

No. 494,075. Patented Man 21,1893.

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IINTTE y STATES PATENT OFFICE.

JAMES SPENCER PARMENTER, OF VVOODSTOCK,` CANADA.

COMPOUND ENGINE.

SPECIFICATION forming part of Letters Patent No. 494,075, dated March 21, 1893.

Application filed June 20, 1892. Serial No. 437,237. (No model.)

compound engines and the object of the in vent-ion is to construct an engine-irst-in which the back pressure will be entirely relieved from the pistons of the high pressure cylinders and-secondly-, in which the area of the high and low pressure pistons will be submitted to the action of the vacuum produced by the condensing chamber and therebyin bothcases minimize the amount of steam and consequent power necessary for the propulsion of the engine and it consists essen.- tially--rst-of providing two high pressure cylinders to act with the low pressure cylinder, the said high pressure cylinders being each provided with one inlet port and two outlet ports one ateach end of the high pressure cylinders, one of each pair of ports being provided with a valve and each pair being connected together and to the low pressure cylinder by a common pipe and-secondly-in connecting each pair of outlet ports, which are connected to the low pressure cylinder, to the condensing chamber by pipes provided with suitable valves one pipe and valve being provided for each pair of outlet ports, the whole being arranged to co-act in the manner hereinafter more particularly explained.

The drawing represents a. diagrammatic Sectional view showing the arrangement of my engine.

A, and, B, are the high pressure cylinders, and, C, is the low pressure cylinder. A', and,

' B', are the high ressure `istons and C' is the low pressure piston. It will be noticed that the pistons, A', B', and, C', are all located on the same piston rod, D, thereby forming what is commonly known as a tandem compound engine.

outlet ports of the high pressure cylinder, B.

-The outletk ports, H, and, I, are provided with exhaust valves, H', and, I'. The ports, Gr, and, H, are connected together by the pipe, K, and the ports, I, and, J, are connected together bythe pipe, L. The pipes, K, and, L, extend into the pipes, M, and, N, which form the ports of the low pressure cylinder and extend from it to the pipe, O, leading into the condensing chamber, P.v AThe pipes M, and, N, are provided with exhaust ports, M', and, N', as shown.

Having now described the general arrangement of .my engine I shall proceed to describe its action. tion in which the pistons are placed the live steam is supposed to be entering through the `port, F, into the high pressure cylinder, B,

the valve, F', being now opened. When the live steam enters through the port, F, it actuates upon the piston, B', and forces it in the direction indicated by arrow until it reaches the port, J, at which period the live steam that indicated by arrow. Simultaneously with the throwing open of the valve, E',occurs the opening of the valves, I', of the exhaust port I, and closing of the valve, N', on the pipe, N. It will now be seen that when the piston, B', is being forced in the opposite direction to that vindicated by arrow the steam in the cylinder, B, will be forced throughy the port, I, and valve, l', pipe, L, and port, J,into the opposite end of the cylinder, B, thereby equalizing the pressure upon the piston, B'. The expansive force of the steam will cause it to enter through the pipes, L, and, N, into the low pressure cylinder, C, and actuate the piston so as to further augment the action of the live steam upon the piston, A', of the high pressure cylinder, A. As soon as the piston A', reaches the port, G, the live steam is cutoff by the valve, E', being closed. Simultaneously with the closing of the valve, E', the valve, H', of the port, H, is opened, the valve, M', on the pipe, M, is closed, valve, I', of the port, I, is closed and the valve, F', of the port, F, is opened. Thelive steam now enters through In the drawings the posi- ICO the port, F, and forces the piston again in the direction indicated by arrow forcing the dead steam which is at the opposite end of the piston, B', in the cylinder, B, through the port, J, pipe, L, and the valve, N', now open, down through the pipe, N, and, O, into the condensing chamber, P, thereby producing a vacuum in the pipes, O, and, N, and cylinder, C, which vacuum acts upon the piston, C', drawing it in the direction in which the piston, B', is forced by the live steam and thereby augmenting the force of the steam on4 the piston, B', so as to force the piston rod in the direction indicated by arrow. During the period that the piston, B', and piston, C', are being forced so as to throw the rod in the direction indicated by arrow, the piston, A', which is moving also in the same direction forces the steam in the cylinder, A, through the port, H, and Valve H', which is now open, through the pipe, K, back into the opposite end of the cylinder, A, thereby equalizin g the pressure on the cylinderand also through the other end of the pipe, K, and pipe, M, up into the low pressure cylinder, C, against the piston, C', augmenting the action of the vacuum upon the piston, C', and forcing the piston, C', in the direction in which the piston rod is being forced by the piston, B', of t'ne high pressure cylinder, B. Vhen the piston, B', of the high pressure cylinder, B, has reached the port, J, the Valves, F', N', and, H', are closed and the valves, E', M', and, l', are opened and as the live steam enters through the port, E, and forces the piston, A', of the cylinder, A, in the opposite direction to that indicated by arrow the steam in the cylinder,

A, at the opposite end of the piston, A', is

forced through the pipe, K, into the pipe, M, down through the pipes, M, and, O, to the condensing chamber, P, which condenses the steam and produces vacuum through the pipes, O, M, and cylinder, C, thereby drawing the piston, C', in the samedirection as the piston, A', is forced by the live steam. During this period the piston, B', of the cylinder, B, moving in the opposite direction to that indicated by arrow forces the steam in the cylinder, B, through the valve, I, and pipe, L, to the opposite end of the cylinder, B, thereby equalizing the pressure upon the piston, B', at the same time allowing of the expansion of the steam to operate upon the piston, C', so as to force it in theA direction in which it is being thrown by the vacuum produced in the pipe, M, in the same manner as hereinbefore stated. This co-acting of the valves is repeated at each time the pistons reach the end of their stroke and consequently a reciprocating movement is imparted to the piston rod, D. It will also be understood that when the valves, F', N', and, H', are open the valves,

E', M', and, I', are closed and vice versa.

Although I have shown my invention applied to a tandem compound engine it will of course be understood that it may with equal facility be applied to a cross compound engine.

What I claim as my invention is- In a compound engine the combination with the low pressure cylinder and piston, of two high pressure cylinders and pistons arranged to coact therewith, a single inlet port leading to the inner end of each high pressure cylinder provided with a suitable valve, pipes K, and L, connecting the outer ends of the low pressure cylinders with the outer ends of the high pressure cylinders, exhaust pipes H, and I, connecting the inner ends of the high pressure cylinders with the pipes K, and L, provided with suitable cnt olf valves, and exhaust pipes connecting the pipes K, and L, with the condenser, with suitable cut off valves located in said exhaust pipes, substantially as described.

JAMES SPENCER PARMENTER. 

